hfsplus: write up fsync for directories

fsync is supposed to not just work on regular files, but also on
directories.  Fortunately enough hfsplus_file_fsync works just fine
for directories, so we can just wire it up.
Signed-off-by: NChristoph Hellwig <hch@tuxera.com>

fs/hfsplus/dir.c

@@ -485,6 +485,7 @@ const struct inode_operations hfsplus_dir_inode_operations = {
 };
 
 const struct file_operations hfsplus_dir_operations = {
+	.fsync		= hfsplus_file_fsync,
 	.read		= generic_read_dir,
 	.readdir	= hfsplus_readdir,
 	.unlocked_ioctl = hfsplus_ioctl,

fs/hfsplus/hfsplus_fs.h

@@ -352,6 +352,7 @@ int hfsplus_cat_read_inode(struct inode *, struct hfs_find_data *);
 int hfsplus_cat_write_inode(struct inode *);
 struct inode *hfsplus_new_inode(struct super_block *, int);
 void hfsplus_delete_inode(struct inode *);
+int hfsplus_file_fsync(struct file *file, int datasync);
 
 /* ioctl.c */
 long hfsplus_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);

fs/hfsplus/inode.c

@@ -302,7 +302,7 @@ static int hfsplus_setattr(struct dentry *dentry, struct iattr *attr)
 	return 0;
 }
 
-static int hfsplus_file_fsync(struct file *file, int datasync)
+int hfsplus_file_fsync(struct file *file, int datasync)
 {
 	struct inode *inode = file->f_mapping->host;
 	struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);